The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Following the development of information and communication technology, including the Internet, communication is on the rise in the form of video as well as text and voice. Users unsatisfied with existing text-oriented communication services are being offered an increasing number of multimedia services encompassing texts, images, music, and various types of information. The enormous quantity inherent to multimedia data calls for larger storage capacities and broader bandwidths. Therefore, compression coding technologies have become a requisite in transmitting multimedia data including text, video and audio.
A basic principle of data compression includes a process of removing data redundancy. Data can be compressed by removing spatial redundancy such as a case where the same colors or objects are repeated in an image, temporal redundancy such as a case where adjacent frames are hardly changed in a video frame or a case where the same notes are repeated in an audio, or psychological vision redundancy considering the fact that human's visual and perceptive abilities are insensitive to high frequencies.
As compared with the existing MPEG-4 (Moving Picture Experts Group-4), the latest H.264/AVC (Advanced Video Coding) video compression method has attracted much attention because of its high compression efficiency. As one of schemes for improving compression efficiency, H.264 uses a directional intra prediction (hereinafter, simply referred to as an intra prediction) in order to remove spatial redundancy from each frame.